Chisel and plane bit sharpener



March 15, 1955 G. A. SMITH 2,703,951

CHISEL AND PLANE BIT SHARPENER Filed May 11, 1953 Fig IN V EN TOR.

Gab/9e A. Sm/fh United States Patent CHISEL AND PLANE BIT SHARPENER George A. Smith, San Francisco, Calif.

Application May 11, 1953, Serial No. 354,147

1 Claim. (Cl. 51-158) This invention relatesto improvements in sharpening devices and has particular reference to a device for sharpening chisels and plane bits.

The principal object of this invention is toprovide a device which will hold and maintain a tool to be sharpened in a definite position and at a definite angle during the moving of the tool over a stone, using a reciprocating movement.

A further object is to provide means whereby the tool may be held in the device at various angles.

A further object is to provide means whereby a constant pressure is maintained between the tool and the cutting stone. 1

A further object is to provide means for constantly applying a lubricant to a stone and removing the excess lubricant so as to eliminate heating of the tool during the grinding operation.

Other objects and advantages will be apparent during the course of the following description.

In the accompanying drawings forming a part of this specification and in which like numbers are employed to designate like parts throughout the same,

Fig. 1 is a side elevation of my device;

Fig. 2 is a cross sectional view taken on the line 2-2 of Fig. 1 and looking in the direction of the arrows;

Figs. 3 and 4 are fragmentary cross sectional views on a large scale, showing the angular position of the tool being sharpened.

Ordinarily, in order to sharpen a plane bit, chisel or the like, the user of the tool merely rubs the cutting face of the tool back and forth across a stone so that a sharp cutting edge is produced.

It is almost impossible to sharpen a tool without a slight rocking motion of the hands that hold the tool and consequently the ground surface is slightly rounded or beveled from side to side.

Or, if the user neglects to put oil on the stone, or rubs too fast, it may become possible that the tool will become heated and will lose part of its temper.

Applicant has therefore devised an arrangement where by the tool is accurately held, moved back and forth with even pressure at a uniform speed, and the lubricant is applied to the cutting surface so as to remove heat and at the same time to keep the surface of the stone clean.

In the accompanying drawings, wherein for the purpose of illustration is shown a preferred embodiment of my invention, the numeral 5 designates a base in which is mounted a receptacle 6 to receive oil through a pipe 7 from an inclined pan 8.

This pan is recessed in the top of the base 5 as best shown in Fig. 2.

At 9 I have shown a cutting stone which is held in the recess by spacer blocks 11 and 12, which blocks have slots 13 formed along the edges adjacent the stone, which permits oil on the stone to drain into the pan 8 and into the receptacle 6.

Mounted on the base are rails as shown at 14 and 16, which rails serve to support wheels 17 and 18, respectively, of a carrier 19.

2,703,951 Patented Mar. 15, 1955 This carrier is connected by a rod 21 to a motor whereby the carrier may be reciprocated on the rails 14 and 16. This carrier has an inclined surface 22 against which the tool to be sharpened may be directly positioned as shown in Fig. l, the tool being designated by the letter A. Or, a wedge-shaped block 23 may be inserted beneath the tool as shown in Figs. 3 and 4. By reversing the position of this block 23, the angle of the tool will be varied as shown in these last mentioned figures.

The carrier has a pair of upstanding arms 24 and 26 which serve to support an oil reservoir 27 which has a pipe 28 extending downwardly and adapted to discharge a drop of oil at a time to the surface of the stone 9.

Thumb screws 29 serve to clamp the tool to the carrier. A cross bar 30 carried by the upstanding arms serve to support wheels 32 and 33 which underlie rods 34 and 36, respectively. One end of these rods is connected to a cross rod 37, the ends of which are engaged by springs 38 the tension of which is adjustable through thumb screws 39, carried in the upper end of standards 41.

The opposite ends of these rods 34 and 36 are connected by a cross piece 42, which is adapted to be engaged by a compression spring 43 mounted upon rod 44 pivoted to the base 5.

This spring 43 is adjusted through the medium of a wing nut 46.

The result of this construction is that when the tool is clamped on the carrier and the carrier is reciprocated, the face of the tool will be moved over the stone at a definite rate and with a definite downward pressure. At the same time, oil will be fed to the cutting surface and excess oil drained away from the stone into the receptacle 6.

When it is desired to remove the tool, the spring 43 can be swung away from the cross piece 42 and the rods 34 and 36 can be swung upwardly to the dotted line position shown to the right of the drawing, after which the tool may be readily removed.

Or the carriage as a whole may be pivoted upwardly so as to inspect the work being done.

Having thus described my invention, I claim:

A sharpening device of the character described, comprising a base, a sharpening stone mounted on said base, a pan formed beneath said stone and communicating with a receptacle formed in said base for receiving drained oil from said stone, a tool-carrier mounted above said stone, means for clamping a tool on said carrier, and means for reciprocating said carrier and pressure means mounted on said base and comprising a pair of spaced standards positioned at one end of said base, a pivoted rod mounted in the other end of said base and centrally positioned with relation to the width of said base, a pair of resilient rods, each having one end adjustably and resiliently carried by said standards and having their opposite ends secured to a cross piece resiliently slidable on said rod, and rollers carried by said tool-carrier for engaging the under-surface of said rods.

References Cited in the file of this patent 

